关于大批填充材料机械性能新测试程序的建议
Matea Macan1, Ana Marošević1, Bruno Špiljak1
1Department of Endodontics and Restorative Dental Medicine, School of Dental Medicine, University of Zagreb, 10000 Zagreb, Croatia.
Materials (Basel, Switzerland)
|July 14, 2023
概括
标准的2毫米聚合法在散装复合材料中产生了更高的转换度 (DC) 和微硬度. 然而,快速的4毫米聚合能在老化后实现了可比的屈曲强度,符合ISO 4049标准.
科学领域:
- 牙科材料科学 牙科材料科学
- 聚合物化学 聚合物化学
- 生物材料工程 生物材料工程
背景情况:
- 大量填充复合材料提供更快的临床应用,但需要适当的聚合.
- 确保足够的固化深度和材料特性对于临床成功至关重要.
- ISO 4049为牙科材料的测试提供了标准,包括曲性质.
研究的目的:
- 为了比较使用不同协议聚合的散装复合材料的柔性特性,微硬度和转换度 (DC).
- 评估快速聚合和加速老化对这些特性的影响.
- 在临床相关条件下评估符合ISO 4049要求.
主要方法:
- 使用2毫米和4毫米厚的样本测试了五种散装复合材料.
- 聚合协议包括标准ISO (2mm,1000mW/cm2,双面),快速10s (4mm,1000mW/cm2,单面) 和快速3s (4mm,2600mW/cm2,单面).
- 转换度 (DC) 通过FTIR测量;曲性质和维克斯微硬度经过1天,1万个热循环和1万个热循环以乙醇浸泡后进行测试.
主要成果:
- 与4毫米标本相比,标准ISO协议导致更高的直流和微硬度.
- 对于标准ISO协议来说,弹性模量显著更高.
- 在老化和乙醇浸泡后,协议之间的屈曲强度差异减少,所有材料都符合80 MPa的ISO 4049要求.
结论:
- 标准的2mm聚合提供了优越的直流和微硬度.
- 快速的4mm聚合,特别是3s协议,实现了可接受的机械性能,并满足老化后的ISO 4049曲强度要求.
- 虽然弹性模量在4毫米样品中减少,但快速聚合是批量填充复合材料的可行选择.
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